build: Downgrade to Java 1.7

Downgrading is necessary to keep compatibility with Android

Change-Id: I9269d3ec32fd87bdd487ec91fab0f6fa87c7de23
diff --git a/pom.xml b/pom.xml
index 5e4b3b1..ef45a8f 100644
--- a/pom.xml
+++ b/pom.xml
@@ -53,8 +53,8 @@
 	</dependencies>
 	<properties>
 		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-		<maven.compiler.source>1.8</maven.compiler.source>
-		<maven.compiler.target>1.8</maven.compiler.target>
+		<maven.compiler.source>1.7</maven.compiler.source>
+		<maven.compiler.target>1.7</maven.compiler.target>
 	</properties>
 	<build>
 		<plugins>